PR644-223603-R01 Developing Corrosion Control Monitoring Technology for Hazardous Liquid Breakout Tanks

Soil-side corrosion monitoring of the aboveground storage tanks (ASTs) is challenging as access to the tank pad environment is not readily available, and the pad conditions can vary throughout the tank diameter. The objective of this work was to research and identify validated technologies to monitor the corrosion conditions under the bottoms of the breakout tanks then develop successful monitoring programs and processes. Monitoring of the undertank corrosion conditions could provide the following three critical assessments to the tank operators: (i) whether the active corrosion control methods are adequate or not, (ii) corrosivity trending of the tank pad material over time, and (iii) need for implementation of the additional corrosion control measures such as vapor corrosion inhibitors (VCIs) to mitigate corrosion. This research comprised of field testing utilizing in-service ASTs, plus laboratory testing and evaluations. Various corrosion control monitoring methods were evaluated as part of the field testing. The monitoring data from field testing was used to develop guidelines for soil-side corrosion monitoring and to develop new design concepts that can be included during the tank construction phase, or retrofitted into the tank pad of operating ASTs, and are conducive to the tank pad corrosivity monitoring. Large-scale experiments were used to determine the VCI dispersion range in highly corrosive conditions, with chloride levels being more than 100 ppm, and was found to be 15-35 ft. It was further determined that effective monitoring can be used to determine the VCI reinjection intervals. The intended audiences of the work documented in this report include AST operators across multiple industries, such as midstream operators and crude oil refineries.